Deepest Look Into Space Finds Billions More Galaxies

Hubble Photos' Detail Excites Astronomers

January 16, 1996|By New York Times News Service.

SAN ANTONIO — As if peeking through a keyhole on the inner sanctum of the universe, the Hubble Space Telescope focused for 10 consecutive days last month on one especially narrow sector of the sky, taking long-exposure photographs deeper into space than ever before achieved and recording the bewildering number and variety of galaxies stretching back toward the beginning of time.

One thing was stunningly clear: With this one achievement, the estimated galactic population of the universe has multiplied enormously--to 50 billion, five times as many as previously estimated.

The sun is one of 50 billion to 100 billion stars in the Milky Way, generally considered to be an ordinary galaxy.

Astronomers, clearly excited, made public a glittering mosaic of the pictures Monday at a meeting of the American Astronomical Society.

They described it as the deepest, most detailed view of the universe ever attained by optical astronomy.

Robert E. Williams, director of the Space Telescope Science Institute in Baltimore, said that this narrow segment of space "will become the most intensively studied region in the sky in the coming decade."

The observed slice of the heavens was no wider than a 25th of one degree, equivalent to the size of a grain of sand held at arm's length. Yet in that space, astronomers reported counting 1,500 to 2,000 galaxies.

Some are so small or far away that they are 4 billion times fainter than the dimmest object the naked eye can see from the ground, 10 times fainter than the deepest existing ground-based observations have detected.

Astronomers are not sure whether they have finally glimpsed the earliest epoch of galaxy formation, which is thought to have begun when the universe was much smaller and no more than 5 percent to 10 percent of its present age.

But they expected that more detailed analysis of these pictures and further Hubble photography of the same region, combined with observations by some of the world's most powerful ground-based telescopes, should lead to a better understanding of how galaxies form and evolve and when these processes began in the young universe.

"We now find there are as many galaxies in the sky as there are stars in our own galaxy," Andrew Fruchter, an astronomer at the space telescope institute, said in an interview.